Once again, George N. Lewis and Theodore A. Postol are asserting that midcourse missile defense interceptors will not work. This latest attack on the missile defense program is in a piece appearing in the current issue of Arms Control Today, which is a publication of the Arms Control Association. This time, however, they focus more attention on the Standard Missile-3 (SM-3) interceptor that is at the heart of the Obama administration’s Phased Adaptive Approach to missile defense. At the technical level, Lewis and Postol assert that midcourse interceptors are insufficiently accurate to target missile warheads on a reliable basis and can be easily fooled by simple countermeasures. They make these claims on the basis of their observations of video clips and data from earlier intercept tests released by the Missile Defense Agency, which they also claim show that missile defense tests the Missile Defense Agency identified as successful were failures.

The Missile Defense Agency’s spokesman, Richard Lehner, responded with a highly technical, and convincing, rebuttal.  Lehner points out that classified telemetry data and sensor views from the tests that the Missile Defense Agency identified as successful showed complete destruction of the targets. Regarding the question of countermeasures, the targets used in the test were “threat representative.” This means that they reflect the capabilities of missiles that are assessed to be available to the potential enemies of the United States. Lehner’s description of the tests make it clear that the Missile Defense Agency and the Navy are on the right track in developing and fielding existing and future versions of the SM-3 interceptor.

The criticisms by Lewis and Postol again raise the question of whether they do not like the missile defense program as a matter of policy and are looking for technical arguments to fit their policy preference. If they want to make a policy argument against the current missile defense program, then they ought to limit themselves to the policy arguments that are included in their piece.

The one positive aspects of the piece by Lewis and Postol, unfortunately, is relegated to a footnote. The authors acknowledge that there is merit to a missile defense system that would use drones to launch interceptors against ballistic missiles in their earliest stages of flight. This approach deserves favorable consideration and the Missile Defense Agency and the Air Force should develop it, but not at the expense of the SM-3 program.